ARC LS22 and pre tubes


I am looking for 8 "good tubes" to replace the eight Sovtek 6922 with a low budget. Please give me an advice.

Thanks
bartlett
Thank you to all. Actually, comparing to McIntosh C20 preamp, ARC LS22 ( I just bought) is lacking of high and low frequency. It is OK in term of noise ( I think it is better than Mc Intosh C20). So, I am not sure what causes the problems I hope replacing tubes will fix the problem! I am going to try some tubes and let you guys know the results. Feel free to recommend.

Thanks
Hi Elevick,

Thanks for your tip. Do you know exactly how many tube (and which ones) used in LS22 for unbalance? I don't use balance cables so i can forget it and just replace tubes that i need. In the other words, which tubes are for balance purposes?
Thanks for your help.
You need the manual or schematics usually. AR will help if you call them. You need a pair of tubes for the gain stage (Most likely the pair closest to the outputs) and a pair for each input. The sockets should be labeled in some way such as v1, v2, v3 and so on.
If you only use cd, you only need 4 tubes.
Ls22 has a pair of input tubes then 2 pairs of voltage gain tubes then a pair of Cathode Followers. The tubes have 2 channels per se and the Balanced uses both for a extra 6db of gain vs the unbalanced inputs.
So V1 and V2 are most important to be quiet and have the sound you like and V3-V6 will increase the gain and shape the sound some more. And maybe someone can learn me on what is important about the Cathode Follower positions.......